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United States Patent |
5,649,915
|
Chauvette
,   et al.
|
July 22, 1997
|
Flexible absorbent sheet
Abstract
A highly absorbent, flexible and resilient sheet comprising a
non-defiberized cellulosic pulp board containing effective amounts of
debonding agent and cross-linked cellulosic fibers, well-suited for use as
an absorbent component of a disposable, absorbent product such as a
sanitary napkin, a diaper, an incontinence pad, an adult brief, a wound
dressing and the like. The invention also extends to a method for
manufacturing the fluid-absorbent sheet, to a disposable absorbent product
utilizing the fluid-absorbent sheet and to a method for enhancing the
resilience, fluid-absorbency and flexibility of a non-defiberized
cellulosic pulp board.
Inventors:
|
Chauvette; Gaetan (Lonevevil, CA);
Ramacieri; Patricia (Montreal, CA)
|
Assignee:
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Johnson & Johnson Inc. (Quebec, CA)
|
Appl. No.:
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481019 |
Filed:
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June 7, 1995 |
Current U.S. Class: |
604/375; 604/367; 604/374 |
Intern'l Class: |
A61F 013/15; A61F 013/20 |
Field of Search: |
604/358,367-368,372,374,375
|
References Cited
U.S. Patent Documents
4605402 | Aug., 1986 | Iskra | 604/368.
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4610678 | Sep., 1986 | Weisman et al. | 604/368.
|
Primary Examiner: Zuttarelli; P.
Attorney, Agent or Firm: Barr; James P.
Parent Case Text
This is a division of application Ser. No. 07/732,852 now abandoned, filed
Jul. 19, 1991, which is hereby incorporated by reference.
Claims
We claim:
1. A resilient, flexible, fluid-absorbent sheet for use in a disposable
fluid-absorbent product, comprising a non-defiberized, cellulosic pulp
board containing effective amounts of a debonding agent and cross-linked
cellulosic fibers, wherein said debonding agent is present in said
cellulosic pulp board in the range from about 0.05 to about 10 percent
based on the dry weight of cellulose in said pulp board.
2. A fluid-absorbent sheet as defined in claim 1, wherein said
fluid-absorbent sheet is mechanically tenderized to enhance its
flexibility.
3. A fluid-absorbent sheet as defined in claim 2, wherein said sheet is
mechanically tenderized by a process selected from the group consisting of
peri-embossing and microcorrugating.
4. A fluid-absorbent sheet as defined in claim 1, wherein said cellulosic
pulp board contains cross-linked cellulosic fibers in the range from about
1 to about 99 percent based on the dry weight of cellulose in said pulp
board.
5. A fluid-absorbent sheet as defined in claim 1, wherein said cross-linked
cellulosic fibers comprise cellulosic fibers treated with an aqueous
solution of a glycol and dialdehyde.
6. A fluid-absorbent sheet as defined in claim 1, wherein said debonding
agent is hydrophilic.
7. A fluid-absorbent sheet as defined in claim 1, wherein said cellulosic
pulp board includes a material selected from the group consisting of
sulfate, sulfite, debonded, bleached, unbleached, Kraft wood pulp,
thermo-mechanical pulp, chemical thermal mechanical pulp, wood pulp
bleached by a chlorine process and wood pulp bleached by hydrogen peroxide
and mixtures thereof.
8. Packaging material comprising the fluid-absorbent sheet of claim 1.
9. A tampon comprising the fluid-absorbent sheet of claim 1.
Description
FIELD OF THE INVENTION
The invention relates to the art of manufacturing structures for absorbing
body exudate. More specifically, the invention relates to a highly
absorbent, flexible and resilient, non-defiberized cellulosic pulp
material providing a soft, fluid-absorbent component, well-suited for use
in disposable absorbent products such as sanitary napkins, diapers,
incontinence pads, adult briefs, wound dressings and the like. The
invention also extends to a method for manufacturing the fluid-absorbent
cellulosic pulp material, to a disposable absorbent product utilizing the
fluid-absorbent cellulosic material and to a method for enhancing the
resilience, fluid-absorbency and flexibility of non-defiberized cellulosic
pulp material.
BACKGROUND OF THE INVENTION
Many disposable absorbent articles use cellulosic pulp fluff material as
the absorbent core. Such cores are generally soft, flexible and absorbent
but tend to be bulky and thick and have poor wicking properties. In
addition, cellulosic pulp fluff cores have poor structural stability,
prone to collapsing when wet.
An absorbent structure that has poor wicking properties may increase the
likelihood of failure of the absorbent product to hold and contain body
fluids. Body fluids will be localized to a certain area of a poorly
wicking absorbent core, causing saturation in such area whereby excess
fluid may overflow through an external surface of the absorbent product.
This overflow may contact the user's garment and cause stains or contact
the user's body and cause wet discomfort or rash. It is therefore
desirable to provide an absorbent core for disposable absorbent articles
which can wick away body fluids from the point of contact with the
absorbent core and spread it through the absorbent core to more
efficiently utilize the entire surface area of the absorbent core. The
improved wicking properties of such an absorbent core provide the capacity
for fluids to travel by capillary action throughout the surface area of
the absorbent core and thus permit the use of thinner cores, since more
absorbent volume can be made available for absorbing body fluids by such
wicking action. Thinner absorbent cores may prove to be more comfortable
for the user and less unsightly or obvious when worn under clothes.
Absorbent cores with excellent wicking properties comprising peat moss and
wood pulp composite materials are described, for example, in U.S. Pat.
Nos. 4,170,515; 4,226,237; 4,215,692; 4,507,112; 4,676,871; and 4,473,440.
In accordance with the teaching of these patents, an absorbent structure
comprising peat moss as a primary absorbent component is formed as a sheet
by air or wet laying of fibers and calendering the sheet to obtain a
relatively thin, i.e. from about 0.01 to 0.1 inch (in) thick and
relatively dense, i.e. from about 0.2 to 1.0 gram per cubic centimeter
(g/cc) structure. Such absorbent peat moss sheets may be processed to
increase their flexibility by subjecting the sheets to mechanical
tenderizing such as by perf-embossing processes as described in U.S. Pat.
No. 4,596,567 or micro-corrugating processes as described in U.S. Pat. No.
4,605,402.
The peat moss sheets thus formed have a large proportion of extremely tiny
pores and capillaries which give them the ability to absorb and retain an
enormous capacity of fluid. The peat moss pores swell as they absorb
fluid, however, this swelling does not cause a loss of capacity for
further absorbing fluid. Rather, the swelling contributes to the ability
of the sheet to retain fluid while generally maintaining the structural
integrity of the absorbent structure in use.
The wicking properties of the above-described peat moss sheets provide the
ability for the sheets to be highly absorbent and thin. The flexibility of
peat moss sheets may be improved by perf-embossing and/or
micro-corrugating processes as described above.
While peat moss sheets make excellent absorbent and wicking cores for
disposable absorbent articles, they have limitations. Peat moss sheets may
not be readily available particularly in areas which lack the critical raw
material, i.e. peat moss or sphagnum moss of desirable age, structure and
moisture content. Peat moss sheets also are relatively dark in color and
may not be aesthetically acceptable for use in all absorbent products.
Having regard to the foregoing, it is desirable to provide a thin,
absorbent and wicking core for disposable absorbent articles which may be
substituted for peat moss sheets or cellulosic pulp fluff sheets.
Attempts to utilize other cellulosic pulp materials such as Kraft wood pulp
boards as absorbent cores have not been successful because they tend not
to have as much absorbent capacity as peat moss composite sheets but more
importantly Kraft wood pulp boards cannot be sufficiently softened for
their intended use. While the flexibility and other characteristics of
such Kraft wood pulp boards may be improved by perf-embossing and/or
microcorrugating techniques, such products still do not provide a
desirable combination of absorption capacity and fluid penetration,
wicking rates and most importantly a sufficient degree of flexibility for
optimal use in disposable absorbent products, including packaging
materials, tampons and particularly sanitary napkins.
It is, therefore, an object of the present invention to provide a
fluid-absorbent cellulosic pulp sheet which does not utilize peat moss in
its structure but has sufficient absorption capacity as well as a
relatively short fluid acceptance time, and possesses good flexibility and
resiliency for use in disposable absorbent articles. Optimal flexibility
of such products requires that the product be comfortably soft and
flexible to the wearer but stiff and strong enough to withstand bunching
and breakage when subjected to mechanical stress in a dry and a wet state.
Another object of the invention is to provide a method for manufacturing
such fluid-absorbent cellulosic pulp sheet.
Another object of the invention is to provide a disposable absorbent
product which uses such cellulosic pulp sheet as an absorbent component.
Yet, another object of the invention is a method for enhancing the
flexibility, resiliency and fluid-absorbency characteristics of
non-defiberized cellulosic pulp material.
SUMMARY OF THE INVENTION
Traditionally, cellulosic pulp fluff has been manufactured by grinding a
high density cellulosic pulp board in a mill which mechanically ruptures
the physical interfiber bonds to produce a fibrous network, the so-called
"fluff", with a very high void volume. An important economic factor in any
process to convert cellulosic pulp boards into fluff material is the
energy cost for operating the grinding mill. It is generally accepted that
regardless of the kind of equipment used for the conversion, the cost of
energy is a significant factor in the overall conversion expenditure.
To reduce the energy consumption of a grinding mill, it is common practice
to incorporate in the cellulosic pulp board a debonding agent which acts
to reduce the forces uniting the cellulosic fibers, by providing a steric
hindrance. As a result, less energy is required to defiberize the
cellulosic pulp board. The most popular debonding agents which are
commercially available from various sources are based on quaternary
amonium compounds. Canadian patent number 1,152,710 granted to
Kimberly-Clark Corporation on Aug. 30, 1983, describes a debonder of this
class. Debonding agents are also described and disclosed in U.S. Pat. No.
4,482,429 at col. 4, lines 8-36; U.S. Pat. Nos. 3,972,855; 4,144,122; and
4,432,833. The entire disclosure of these references are hereby
incorporated by reference. It has also been suggested to treat a
cellulosic pulp board with debonding agent and then perf-emboss the
debonded pulp board to reduce its stiffness to acceptable levels for use
as an absorbent core in a disposable absorbent product. The combination of
debonding and perf-embossing increases the absorption and flexibility of
the cellulosic pulp board.
As a substitute to chemical debonding agents, it has been suggested to
introduce in the cellulosic pulp board cross-linked cellulosic fibers
providing a high-bulk, resilient structure acting to maintain a certain
spacing between the fibers of the cellulosic pulp board, to achieve a
reduction in the cohesiveness of the fibrous network. As an example, the
U.S. Pat. No. 4,853,086 granted to Weyerhaueser Company on Aug. 1, 1989
describes a method for manufacturing such cross-linked cellulosic fibers.
In essence, the method consists of spraying a wet or partially dried web
of cellulosic fibers with an aqueous solution of a glycol and dialdehyde.
The present inventors have made the unexpected discovery that by
incorporating a debonding agent and cross-linked cellulosic fibers to a
board of cellulosic pulp, a synergy effect develops, vastly improving the
resiliency, flexibility and fluid-absorbency (for the purpose of this
specification, "fluid-absorbency" shall solely mean the ability of a body
to take-up fluid, regardless of how fluid-retentive the body is. For
example, the transfer layer of a compound absorbent structure, provided to
meter fluid to the reservoir layer, will be described as fluid-absorbent
although it has a relatively poor fluid retentivity) of the board,
providing a soft, highly absorbent sheet that may be used in a
non-defiberized form as an absorbent component for disposable absorbent
products such as sanitary napkins, diapers, adult briefs, incontinence
pads, wound dressing and the like. A particularly significant advantage of
this absorbent structure resides in that no defiberization is required,
which considerably reduces the manufacturing cost of the absorbent
structure.
The debonding agent (for the purpose of this specification "debonding
agent" should be construed to include any agency acting chemically on the
cellulose fibers to reduce the incidence of hydrogen bonding between the
fibers by steric hindrance action) cooperates with the cross-linked
cellulosic fibers to provide the essential ingredients necessary to relax
the fibrous network of the cellulosic material. More specifically, the
debonding agent weakens the interfiber bonds, while the cross-linked
cellulosic fibers provide, by virtue of their inherent resiliency, an
expansion force pushing the fibers away from one another. The resulting
fibrous network has a void volume which is high enough to provide an
excellent fluid-absorption capacity and a high fluid-acceptance rate,
while remaining below the level beyond which the structural integrity of
the fluid-absorbent sheet is compromised in use. The increase in the
inter-fiber distances also provides the fibrous network with the ability
to flex under low effort and to return to its original configuration upon
the cessation of the deformation effort. These characteristics provide
increased comfort potential allowing the fluid-absorbent, non-defiberized
cellulosic sheet to be used as an absorbent component in disposable
absorbent products for use next to the body.
Interestingly, the fluid-absorbent cellulosic sheet is particularly stable
in a wet condition, exhibiting only a limited collapse upon fluid take-up.
This phenomenon is attributable to the ability of the cross-linked
cellulosic fibers to maintain the fibers of the fluid-absorbent cellulosic
sheet in a spaced apart relationship in the presence of a fluid medium.
In a preferred embodiment, the fluid-absorbent cellulosic sheet comprises
cross-linked, fibrous cellulosic material in the range from about 1 to
about 99 percent based on the dry weight of cellulose. The debonding agent
is present in the fluid-absorbent cellulosic sheet in the range from about
0.05 to about 10 percent based on the dry weight of cellulose.
Advantageously, the fluid-absorbent cellulosic sheet is mechanically
tenderized by perf-embossing or micro-corrugation to increase its
flexibility for further enhancing its comfort potential.
The starting material for manufacturing the fluid-absorbent cellulosic
sheet is preferably selected from the group consisting of sulfate,
sulfite, debonded, bleached, unbleached, Kraft wood pulp,
thermo-mechanical pulp, chemical thermal mechanical pulp, wood pulp
bleached by a chlorine process and wood pulp bleached by hydrogen
peroxide.
As embodied and broadly described herein, the invention further comprises a
method for manufacturing a non-defiberized, fluid-absorbent sheet,
comprising the step of incorporating in a cellulosic pulp board effective
amounts of cross-linked cellulosic fibers and debonding agent to enhance
the resiliency, flexibility and fluid-absorbency of said cellulosic pulp
board.
In a preferred embodiment, the cross-linked cellulosic fibers are added to
a slurry of cellulosic pulp which is used for making the cellulosic pulp
board. The slurry is then formed into a web and dewatered to obtain the
highly resilient and flexible, fluid-absorbent cellulosic sheet. The
debonding agent may be added to the slurry or applied to the web in a
dried or partially dried condition such as by spraying, soaking or
kissing.
As embodied and broadly described herein, the invention also provides a
method for increasing the resilience, flexibility and fluid-absorbency of
a non-defiberized cellulosic pulp board, comprising the step of
incorporating in said cellulosic pulp board effective amounts of debonding
agent and cross-linked cellulosic fibers.
As embodied and broadly described herein, the invention also extends to a
disposable, laminated, fluid absorbent product such as a sanitary napkin,
a diaper, an adult brief, an incontinence pad, a wound dressing and the
like, comprising:
a) a fluid-permeable cover layer;
b) a fluid-impervious backing layer in a generally parallel and spaced
apart relationship with said fluid-permeable cover layer; and
c) an absorbent component between said layers, said absorbent component
comprising a non-defiberized cellulosic pulp board containing effective
amounts of debonding agent and cross-linked cellulosic fibers, enhancing
the resiliency, flexibility and fluid-absorbency of said pulp board.
The fluid-absorbent cellulosic sheet according to the invention may also be
utilized in other absorbent products such as inserts for tampons, or as
desiccants for use in packaging materials to keep goods dry during
shipping or storage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an idealized perspective view at the fiber level of a cellulosic
pulp board in raw form, i.e. free of agents that hinder the hydrogen
bonding between the cellulosic fibers;
FIG. 2 illustrates the network of the cellulosic pulp board of FIG. 1 in
which cross-linked cellulosic fibers have been incorporated;
FIG. 3 is an idealized view of the fibrous network shown in FIG. 2 in which
a debonding agent has been incorporated; and
FIG. 4 is a fragmentary, perspective view of a sanitary napkin
incorporating the fluid-absorbent cellulosic sheet according to the
invention.
DESCRIPTION OF A PREFERRED EMBODIMENT
FIG. 1 is an idealized, perspective view on a highly enlarged scale of the
fibrous network 10 of a cellulosic pulp board in raw form. It should be
understood that this representation is solely for illustrative purposes
and it does not necessarily conform to the true material structure of the
cellulosic pulp board.
The fibrous network 10 is composed of individual cellulosic fibers 12,
which are randomly oriented and are united to one another by hydrogen
bonding. The fibers 12 form a highly dense and cohesive network with only
a limited amount of void volume therebetween. This translates into poor
fluid-absorption properties and into a rigid, relatively non-conformable
structure, making the cellulosic pulp board unsuitable for use as an
absorbent layer in a disposable absorbent product.
In order to reduce the cohesiveness of the fibrous network 10, primarily
for facilitating its mechanical defiberization, the prior art teaches to
incorporate in the fibrous network 10 cross-linked cellulosic fibers
providing a high-bulk, resilient structure which functions to physically
space the fibers 12 from one another.
FIG. 2 illustrates schematically a cellulosic fibrous network 14 containing
cross-linked cellulosic fibers 16. The cross-linked fibers 16, forming a
space frame-like structure are uniformly interspersed with the fibers 12
and, by virtue of their inherent resiliency, urge the fibers 12 away from
one another. However, it is believed that the hydrogen bonding between the
fibers 12 remains very strong and greatly overwhelms the resistance to
deformation of the cross-linked cellulosic fibers 16. As a result, the
space frame-like structure is in a virtually collapsed condition,
achieving only a limited reduction in cohesiveness of the fibrous network
14. The reduction in structural integrity of the fibrous network 14
considerably reduces the energy required to mechanically defiberize it,
however, it does not sufficiently improve its fluid-absorbency, resiliency
and flexibility to allow the fibrous network 14 to be advantageously used
as an absorbent component in a disposable absorbent product.
The method for manufacturing the cross-linked cellulosic fibers 16 will not
be described herein because this technology is well documented in the
patent literature. For example, U.S. Pat. No. 4,853,086 discloses a
process for manufacturing the cross-linked cellulosic fibers by spraying a
wet or only partially dried cellulosic fibrous web with an aqueous
solution of a glycol and dialdehyde. The entire disclosure of this patent
reference is hereby incorporated herein by reference.
FIG. 3 illustrates a cellulosic pulp board treated with a debonding agent
and containing cross-linked cellulosic fibers 16. It is apparent that the
fibrous network 18 is considerably more relaxed than the fibrous network
14, exhibiting comparatively large interfiber distances which translate
into a higher void volume and an increased, overall bulk. The significant
improvement in bulking by comparison to the fibrous network 14 shown in
FIG. 2 is attributable to the debonding agent which inhibits the hydrogen
bonding between the fibers, reducing the forces collapsing the space
frame-like structure formed by the cross-linked cellulosic fibers 16. As a
result, the space frame-like structure expands the entire fibrous network
18 by virtue of its ability of rebound or shape recovery after
deformation.
The fibrous network 18 is advantageous for use in a non-defiberized form as
an absorbent component for a disposable absorbent product such as a
sanitary napkin, a diaper, an incontinence pad, an adult brief, a wound
dressing and the like. It offers exceptional fluid absorption properties
such as a good capacity and a high fluid-acceptance rate as well as good
wicking characteristics. In addition, it has a good comfort potential
because it is soft and flexible, providing an absorbent product which is
highly conformable to the area of the body to which it is intended to be
applied, thus providing good gasketing properties, i.e. the ability to
conform to the surface of the body. In addition, the fibrous network 18 is
capable to maintain its integrity in the dry and in the wet state.
Further, its degree of collapse upon taking-up fluid is relatively small,
providing a good structural integrity in the presence of a fluid medium.
The various fluid-absorbency characteristics of the fibrous network 18 may
be tailored according to the intended application by varying the density
of the fibrous network 18. For example, by decreasing the density of the
fibrous network 18, the fluid-acceptance rate increases at the expense of
fluid retentivity and capacity. Such a structure would be suitable as a
transfer layer in a compound absorbent component for metering fluid to a
reservoir layer. Conversely, an increase of density will favour the
fluid-absorbency requirements for a reservoir layer. For a single layer
absorbent structure, the density is selected to provide the necessary
balance between the various fluid-absorbency characteristics.
The fluid-absorbent cellulosic pulp sheet according to the invention is
manufactured by incorporating into a slurry of cellulosic pulp material
cross-linked cellulosic fibers prepared in accordance with the process
generally set forth in U.S. Pat. No. 4,853,086. The percentage of
cross-linked cellulosic fibers in the slurry is in the range from about 1
to about 99 percent based on the dry weight of cellulose.
The appropriate debonding agent is also added in the slurry of cellulosic
material, in the range from about 0.05 to about 10 percent based on the
weight of cellulose. A hydrophilic debonder has been found satisfactory.
(By "hydrophilic debonder" is meant a debonding agent that preserves the
hydrophilic nature of the cellulosic material). U.S. Pat. No. 4,432,833
discloses various hydrophilic quaternary amine debonders and U.S. Pat.
Nos. 3,972,855 and 4,144,122 disclose various debonding agents including
the commercially available BEROCELL 584 debonding agent which is a
particularly preferred debonding agent for use in the present invention.
The disclosure of the various debonding agents in these patents is hereby
incorporated herein by reference.
The slurry is formed into a web and dewatered to form the fluid-absorbent
cellulosic sheet.
In a variant, the debonding agent may be incorporated into the cellulosic
material after the slurry has been formed into a web. For example, the
debonding agent may be sprayed on one or on both sides of the web, or the
web may be soaked into a solution of debonding agent for a deeper
penetration. Also, a kissing technique may be employed, as described in
Canadian patent number 596,894 issued on Apr. 26, 1960 to Chicopee
Manufacturing Corporation, U.S.A. The entire disclosure of this reference
is hereby incorporated herein by reference.
The starting material for making the slurry of cellulosic material is
selected from the group consisting of sulfate, sulfite, debonded,
bleached, unbleached, Kraft wood pulp, thermo-mechanical pulp, chemical
thermal mechanical pulp, wood pulp bleached by a chlorine process and wood
pulp bleached by hydrogen peroxyde and mixtures thereof.
In order to further tenderize, soften and improve the flexibility of the
fluid-absorbent cellulosic sheet, it may be subjected to mechanical
tenderizing by perf-embossing or microcorrugating processes as generally
described in the United States patents granted to Personal Products
Company, U.S. Pat. Nos. 4,596,567 and 4,559,050, issued on Jun. 24, 1986
and Dec. 17, 1985, respectively (which are hereby incorporated herein by
refeence).
Broadly stated, the perf-embossing operation consists of perforating by
shearing action, at a multiplicity of points the fluid-absorbent
cellulosic sheet to open up its structure by locally disrupting the
integrity of the fibrous network 18. Subsequently, the fluid-absorbent
cellulosic sheet is embossed transversely and longitudinally by passing
the sheet between rolls having intermeshing flutes. The embossing lines
created constitute hinges which considerably enhance the flexibility of
the sheet.
The microcorrugating operation is similar to the perf-embossing process
except that no perforation is performed. The fluid-absorbent cellulosic
sheet is solely subjected to a lateral embossing operation to create
closely spaced hinge lines.
FIG. 4 illustrates a sanitary napkin incorporating the fluid-absorbent
cellulosic sheet according to the invention. The sanitary napkin,
designated comprehensively by the reference numeral 20, comprises an
envelope 22 defining an internal space receiving an absorbent component
24. The envelope 22 includes a fluid-permeable cover layer 25 made of
non-woven fabric or any other suitable porous web, and a fluid-impervious
backing layer 26 made of polyethylene film, for example. The cover and
backing layers 25 and 26 are heat-sealed to one another along their
marginal portions.
The absorbent component 24 may have a single or a double layer
configuration. In the former case, depicted in FIG. 4, the absorbent
component 24 is an insert constituted by the fluid-absorbent cellulosic
sheet according to the invention. In the latter case (not shown in the
drawings), the absorbent component has a top layer, referred to as a
transfer layer and a bottom layer, designated as a reservoir layer. The
fluid-absorbent cellulosic sheet is particularly suitable for use as a
transfer layer due to its high fluid-acceptance rate, coupled in an
intimate fluid-communicative relationship with a reservoir layer made of
any suitable highly absorbent and retentive material. In a variant, the
fluid-absorbent cellulosic sheet may be adapted for reservoir layer duty
or use by increasing its density, as previously described.
To attach the sanitary napkin 20 to the wearer's underpants, the
fluid-impervious backing layer 26 is provided with adhesive zones covered
with a peelable backing (not shown in the drawings).
Sanitary napkins constructed in accordance with the present invention are
found to possess a very high fluid-absorption capacity and a comparatively
high fluid-acceptance rate which reduces the risk of failure when a large
quantity of fluid is suddenly released on the sanitary napkin. In
addition, the sanitary napkin is thin, soft and flexible so as to be
comfortable to the user and to conform well to the surface of the body to
which it is applied to achieve good gasketing effects.
The scope of the present invention is not limited by the description,
examples and suggestive uses herein, as modifications can be made without
departing from the spirit of the invention. Applications of the product
and methods of the present invention for sanitary and other health-care
uses can be accomplished by any sanitary protection, incontinence, medical
and absorbent methods and techniques that are presently or prospectively
known to those skilled in the art. For example, the absorbent products and
methods of the invention can be applied to wound dressings or other useful
absorbent products. Thus, it is intended that the present application
cover the modifications and variations of this invention provided that
they come within the scope of the appended claims and their equivalents.
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